Conduct a search for immune complexes by developing sensitive quantitative methods based on reaction with the Clq component of complement, human monoclonal rheumatoid factors, and the Raji line of lymphoblastoid cells. Do systematic screening of sera from a broad cross-section of patients to establish the presence of circulating immune complexes in cancer. The identity of the complexes shall be extablished by physiochemical and immunochemical studies on representative specimens. Establish the levels of immune complexes in various cancers and compare them to normal subjects and patients with other diseases to reveal the diagnostic and prognostic values of these procedures.